From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: Re: [PATCH] ACPI / CPPC: Use 64-bit arithmetic instead of 32-bit Date: Thu, 8 Feb 2018 10:40:38 -0600 Message-ID: <1f5cffd5-4806-a8e6-48d7-bc2f8ec1d440@embeddedor.com> References: <20180206233617.GA30829@embeddedgus> <2503109.MpnWDuSnnD@aspire.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from gateway36.websitewelcome.com ([192.185.193.12]:27906 "EHLO gateway36.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751544AbeBHRFB (ORCPT ); Thu, 8 Feb 2018 12:05:01 -0500 Received: from cm12.websitewelcome.com (cm12.websitewelcome.com [100.42.49.8]) by gateway36.websitewelcome.com (Postfix) with ESMTP id 08B7C40173478 for ; Thu, 8 Feb 2018 10:40:40 -0600 (CST) In-Reply-To: <2503109.MpnWDuSnnD@aspire.rjw.lan> Content-Language: en-US Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" , "Gustavo A. R. Silva" Cc: Len Brown , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org On 02/08/2018 03:49 AM, Rafael J. Wysocki wrote: > On Wednesday, February 7, 2018 12:36:17 AM CET Gustavo A. R. Silva wrote: >> Add suffix ULL to constant 500 in order to give the compiler complete >> information about the proper arithmetic to use. Notice that this >> constant is used in a context that expects an expression of type >> u64 (64 bits, unsigned). >> >> The expression NUM_RETRIES * cppc_ss->latency at line 578, which at >> preprocessing time translates to 500 * cppc_ss->latency is currently >> being evaluated using 32-bit arithmetic. >> >> Addresses-Coverity-ID: 1382602 >> Signed-off-by: Gustavo A. R. Silva >> --- >> Notice that another option is to cast NUM_RETRIES to u64 at line 578, >> but as there is only one instace in which this macro is being used I >> think adding the ULL is just enough. >> >> drivers/acpi/cppc_acpi.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c >> index 06ea474..0afbb26 100644 >> --- a/drivers/acpi/cppc_acpi.c >> +++ b/drivers/acpi/cppc_acpi.c >> @@ -119,7 +119,7 @@ static DEFINE_PER_CPU(struct cpc_desc *, cpc_desc_ptr); >> * to PCC commands. Keeping it high enough to cover emulators where >> * the processors run painfully slow. >> */ >> -#define NUM_RETRIES 500 >> +#define NUM_RETRIES 500ULL >> >> struct cppc_attr { >> struct attribute attr; >> > > Applied, thanks! > > Thank you, Rafael. -- Gustavo